SOUTH WELLFLEET — A taste of the contemplative solitude that once inspired playwright Eugene O'Neill and poet Harry Kemp awaits you, courtesy of the National Park Service.

Eighteen small, weathered shacks owned by the federal government perch in the dunes above the Atlantic shoreline in Provincetown and Truro, part of the Cape Cod National Seashore. Up till now, their availability has been through a patchwork of administrative instruments. Now, for the first time, a plan is in place to manage their public use.

All 18 shacks are in the 1,960-acre Dune Shacks of Peaked Hill Bars Historic District, which has been formally listed on the National Register of Historic Places since March.

The shacks date from at least the 1920s and were built largely as rustic shelters, without public utilities or road access, for fishermen, shipwreck survivors and sea rescuers. Over time, though, they turned into recreation and artistic retreats for local families and their kin and guests.

Currently, the Seashore has a variety of agreements with families and nonprofits to use the shacks. The new plan, signed on May 18, formalizes the way the shacks will be preserved and used in the future.

The Seashore superintendent will make the decisions for the historic district, and a standing subcommittee of the Seashore Advisory Commission will help carry out the plan.

Shacks that will be used over many years by individual families will have to go through a National Park Service competitive lease program.

The plan is meant to give people the unique chance to experience the contemplative solitude of a dune shack stay and further the historic district's arts and literature tradition.

The plan is also supposed to sustain unique, long-standing relationships of families and friends living in and maintaining some of the shacks, while giving members of the public opportunities to visit and stay in some as well. The plan is supposed to protect the dunes, and devise ways for the shack occupants and the National Park Service to work together to maintain the buildings and the district's cultural history.

Approximately 40 percent of the shacks are set aside for private use, under contracts lasting up to 20 years. Another 40 percent are set aside for nonprofit organizations, under contracts lasting three to 10 years, and the nonprofits would offer a chance for anyone to apply to stay in a shack. The last 20 percent would go to either private families or nonprofits.

Right now, five of the 18 shacks are managed by three local groups. These groups — the Provincetown Community Compact, the Outer Cape Artists in Residence Consortium and Peaked Hill Trust — offer overnight stays for the public by application.

A 19th shack, privately owned, is not covered by the plan.

In the coming weeks, Seashore officials will be looking at existing agreements and leases and also assessing structural needs of the shacks, Seashore Superintendent George Price said last week.

The permanent dune shack subcommittee of the advisory commission still needs to be appointed, said Richard Delaney, commission chairman.

This latest effort for a long-term plan began in 2009 when the Seashore hired a facilitator to help guide the public proceedings. The next step is to see if "all of this will be implementable," said Richard Delaney, chairman of the Seashore's citizen advisory committee.

"We were able to come to an agreement that had been elusive for the last couple of decades," Delaney said Wednesday. "I think everyone is very pleased that we have given the superintendent and the National Park Service a good framework to make the decisions about individual shacks and their future uses."

Julie Schecter, co-founder of the nonprofit Peaked Hill Trust, said the new plan clearly allows short-term stays — something she was surprised and happy to see in writing.

"It gave me a great deal of hope that people will, as they always have, be able to go out and have that experience without, I hate to use this word, without being somebody special," Schecter said. "It's lovely to see that accessibility addressed."

She added that even a short stay in one of the shacks can be "life-changing."

Josephine Del Deo of Provincetown, who uses the shack known as "Chanel," said Wednesday that at first the Park Service wanted to tear down the shacks. Del Deo and her family have lived in and maintained the shack, which has one large room and a small studio, for more than half a century. She has fought in the past four decades to protect the shacks as a historic district.

"We do want to preserve the shacks, and we're thankful that the (national historic district) registration is now official," Del Deo said. But she worries the Park Service is attempting to introduce more short-term rentals of the shacks and fewer long-term leases by families who care about the way of life in the dunes and who take on the responsibility of maintaining the shacks.

"It's much too easy to group these cottages into a consortium of nonprofits and rent them like a concession," Del Deo said.